In the last couple of weeks, I’ve started getting this error ~1/5 times when I try to open one of my own locally hosted services.
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I’ve never used ECH, and have always explicitly restricted nginx to TLS1.2 which doesn’t support it. Why am I suddenly getting this, why is it randomly erroring, then working just fine again 2min later, and how can I prevent it altogether? Is anyone else experiencing this?
I’m primarily noticing it with Ombi. I’m also mainly using Chrome Android for this. But, checking just now; DuckDuckGo loads the page just fine everytime, and Firefox is flat out refusing to load it at all.
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Firefox refuses to show the cert it claims is invalid, and ‘accept and continue’ just re-loads this error page. Chrome will show the cert; and it’s the correct, valid cert from LE.
There’s 20+ services going through the same nginx proxy, all using the same wildcard cert and identical ssl configurations; but Ombi is the only one suddenly giving me this issue regularly.
The vast majority of my services are accessed via lan/vpn; I don’t need or want ECH, though I’d like to keep a basic https setup at least.
Solution: replace local A/AAAA records with a CNAME record pointing to a local only domain with its own local A/AAAA records. See below comments for clarification.